Despite recent advances in cancer research, the development of cell-specific therapies for treatment of malignancies remain elusive. The many and complex factors which enable malignant cells to undergo mutations, evade immune protection and promote angiogenesis to deliver nutrients to the rapidly growing cells complicate the development of targeted treatment modalities. Current therapies have multiple untoward side effects. For example, chemotherapy results in multiple painful and sometimes lethal side effects. Advances in biotechnology have promoted the development of targeted biologicals with fewer side effects.
Host cells have surface receptors that associate with ligands to signal and cause host cell activities. The epidermal growth factor receptor helps control cell growth and metastasis. Many tumor cells express higher numbers of epidermal growth factor receptors than normal cells. A new treatment designated IMC-225 was specifically designed to target and block epidermal growth factor receptors preventing cell division and repair. Recently, trastuzumab, which is a HER-2-specific monoclonal antibody, has proven effective at treating metastatic breast cancers. This antibody blocks interactions on cancer cells that inhibit cell growth. Unfortunately, HER-2 is only found on about 25 to 30 percent of breast cancer cells.
A variety of pathogens or toxins activate macrophages, neutrophils, T cells, B cells, monocytes, NK cells, Paneth and crypt cells, as well as epithelial cells shortly after entry into the mucosa. Chemokines are a superfamily of small, cytokine-like proteins that are resistant to hydrolysis, promote neovascularization or endothelial cell growth inhibition, induce cytoskeletal rearrangement, activate or inactivate lymphocytes, and mediate chemotaxis through interactions with G-protein-coupled receptors. Chemokines can mediate the growth and migration of host cells that express their receptors. The cellular mechanisms responsible for the function of the chemokines are often, but not always, Ca2+ flux dependent and pertussis toxin-sensitive. However, the precise mechanisms for chemokine-mediated events are not known